Method of applying strapping material to round packages or the like

ABSTRACT

A method of and device for strapping round packages, according to which a predetermined section of a strap is advanced into an adjustable strap guide while the latter is in its starting position, whereupon the strap guide is moved into contact with the circumference of the package to be strapped and an additional strap section is passed through the strap guide so that the strap extends completely around the package to be strapped. The strap around the package is then tightened and sealed. The strap guide comprises a plurality of segments pivotable relative to each other.

O United States Patent [1 1 [1111 3,867,878

Bulme 1 Feb. 25, 1975 METHOD OF APPLYING STRAPPING 2,831,422 4/1958 Black et a1 100/25 MATERIAL o ROUND PACKAGES 2,959,118 11/1960 Hager 100/26 THE LIKE 3,234,870 2/1966 Mtss oux 100/26 3,279,355 /1966 MlSSlOLlX 100/26 [75] Inventor: Gerd Buhne, Schwelm, Germany 3,362,321 1/1968 Lindholm et a1. 100/26 X [73] Asstgnee: gitm Yerpackungs System GmbH, Primary Examiner Billy J wmme c we Germany Attorney, Agent, or Firm-Walter' Becker [22] Filed: Feb. 26, 1973 211 App]. No.2 335,828 [57] {*BSTRACT A method of and device for strapping round packages, according to which a predetermined section of a strap Foreign Application Priority Data is advanced into an adjustable strap guide while the Feb. 26, 1972 Germany 2209120 latter is in its starting position, whereupon the strap guide is moved into contact with the circumference of [52] U.S. Cl 100/2, 100/7, l0O/25 the package to be strapped and an additional strap [51] Int. Cl Bb 13/04 section is passed through the strap guide so that the [58] Field of Search lOO/2, 7, 10,25, 26 strap extends completely around the package to be strapped. The strap around the package is then tight- [56] References Cited ened and sealed. The strap guide comprises a plurality UNITED STATES PATENTS of segments pivotable relative to each other.

2,420,498 5/l947 Pojman /25 X 2 Claims, 2 Drawing; Figures PATENTED F552 51975 sum 1 of 2 PATENIEB FEB 2 5 i975 SHEET 2 BF 2 FIG.2

METHOD OF APPLYING STRAPPING MATERIAL TO ROUND PACKAGES OR THE LIKE The present invention relates to a method of applying strapping material to round packages or the like, as for instance coils of rolled sheet metal or paper of different diameters in one single engaging step.

With strapping operations of this type it is intended to apply strapping material in one single engaging step successively to coils of rolled sheet metal of different diameters and with horizontal winding axes.

It is known to strap coils of rolled sheet metal in one single engaging step. However, in this connection a drawback consists in the fact that the strap is guided in a guiding passage which is dimensioned for the maximum possible diameter of a sheet metal coil, and that the strap in order to be able to engage the respective package to be strapped, has to be pulled back to a considerable extent depending on the diameter of the package to be strapped. The pulled back portion of the strap will not be pulled back into the supply roll but onto the floor of the mill, i.e. into the working path of the operators. This represents a source of possible accidents because the men can easily trip over the strap portion lying on the floor. Due to the not very orderly accumulation of the excessive pulled back strapping material, the strapping material may buckle, bend or may otherwise be damaged so that a proper guiding of the strap through the guiding passage will no longer be possible. The elimination of such disorders increases the average time required for the strapping operation which time is already longer in view of the necessary pulling back of the strapping material.

Semiautomatically operating strapping devices for packages are known according to which a boom adjustable as to height and cooperating with elements of the strap guiding means permits the strapping of packages of different sizes. The principle of this device, however, is not advantageously applicable to round packages because the guiding of the strapping material cannot be varied laterally on all sides but only with regard to the length of one side of the approximately rectangular strap guiding passage so that with round packages there is still necessary the pulling back of a considerable length of the strap.

It is, therefore, an object of the present invention to provide a method of applying strapping material to round packages or the like of different diameters in one single engaging step, in which in each instance only the required length of strapping material is fed for the respective strapping operation.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 diagrammatically illustrates a side view of a strap guiding device in a strapping installation according to the invention.

FIG. 2 illustrates a view of the strapping installation of FIG. 1 as seen in the direction of the arrow II of FIG. 1 while the segmental sections occupy the dot-dash line position and no package is being shown.

The method according to the present invention is characterized primarily in that the strap is by a predetermined length advanced in the strap guiding passage in the rest or starting position thereof, whereupon the strap guiding passage is placed against the outer circumference of the respective package to be provided with the strap so as to follow the curvature of the package, and additional length of strapping material is by means of a strap feeding device fed for completion of the strapping operation and is then in a manner known per se tightened and closed.

It is expedient that the advanced length of the strap is adapted to the circumference of the smallest package to be strapped.

The important feature of the device according to the invention for practicing the method outlined above consists in that a stand has arranged therein a plurality of segmental members respectively journalled unilaterally on a pivot and guided relative to each other by means of strips while being adapted to be controlled by a pressure cylinder. These segmental members are adapted to be nested in each other and are provided with rigid and movable magnetic. rollers (FIG. 2).

In order to be able to push the segmental members partially into each other, it is expedient that the movable magnetic rollers which are journalled on resilient levers are adapted to be controlled over a track of the respective lower segmental member. In this connection it is expedient that the movable rollers which are journalled on resilient levers are alternately arranged on the right-hand and the left-hand side plate of the segmental members. To assure a proper guiding of the strap within the guiding means therefor, it is provided that the magnetic rollers are equipped with lateral guiding edges.

Referring now to the drawings in detail, FIG. 1 shows a complete installation for applying strapping material of which stand 1 is the essential element. The base frame of stand 1 comprises two lateral plates 2 between which there are provided three segments 3, 4, 5 which are journalled on pivots 6, 7, 8 respectively. These segments 3, 4, 5 are nested within each other in such a way that the segment 3 is located in the lower portion of the segment 4 between the lateral side walls 9 thereof while the segment 4 is located in the lower portion of the segment 5 between the side walls 10 thereof.

The segments 3, 4, 5 are mutually interconnected by positive guiding means which comprise the guiding strips 11 and guiding rollers 12.

Rotatable magnetic rollers 13 are rigidly mounted on the side walls 14 of the segment 3. Such rigidly mounted magnetic rollers are also provided in the segments 4 and 5. With regard to the segments 4 and 5, these segments are additionally equipped with movably mounted magnetic rollers 15. These magnetic rollers 15 are rotatably journalled on resilient levers 16. The movably journalled magnetic rollers 15, when actuated, are being acted upon by the tracks 17, 18 of the segments 3, 4. The tracks 17, 18 are likewise arranged in the upper rear portion of the segments 3, 4.

The movement of the segments 3, 4, 5 is brought about by a pressure fluid operable cylinder piston system 19 which on the one hand is provided between the lateral plates 2 of stand 1 and on the other hand is provided at the lower rear portion of the segment 5. For guiding the strap, the magnetic rollers 15 are provided with guiding rims or edges 131,151 (FIG. 2).

The operation of the strap guiding device 1 in a complete strap applying installation according to FIG. 2 is as follows. A round package or the like to be strapped and having a horizontal winding axis, for instance, a bale of paper or a coil of rolled sheet metal with a diameter which may vary from a minimum diameter 20 to a maximum diameter 21, is in any convenient manner by a conveyor belt 22 moved into the strapping installation.

By means of any standard control and transport device or manually, a control panel 23 which is displaceable on a rail in the direction of the arrow 24 and to which is connected the strap guiding device 25 is moved onto the package to be wrapped. The strap 26 is withdrawn from an unwinding carriage 27 which is arranged below the floor. Any standard strap feeding device 28 will then feed the strap 26 by a predetermined length into the stand 1, preferably by a length equalling the possible minimum diameter of a package to be wrapped. The segments 3, 4, are supposed to occupy the dot-dash starting position shown in FIG. 1. This is expedient in order to make sure that the strap 26 will not move between the magnetic rollers 13, which in any other position of the segments might easily be the case. After the strap has been advanced by the predetermined length, the pressure cylinder 19 is actuated which then initiates a movement limited by a limit switch, and moves the segments 3, 4, 5, for instance, into the position shown in full lines in FIG. 1. When the pressure fluid operable cylinder piston system expands, the segment 5 moves in counterclockwise direction about the pivot point 8 and brings about a corresponding movement of the segments 4 and 3 in the same direction about the pivot points 7 and 6. This movement is brought about by the positive guiding by means of the guiding strips 11 and the guiding rollers 12. In this way the radius of the strap guiding means decreases. This is made possible due to the fact that the segments 3, 4, 5 are nested in each other and that the tracks 17 and 18 in the respective segments 4 and 5 located thereabove immerse the magnetic rollers 15 which are movably mounted on levers 16 as is shown in solid lines in FIG. 1. After this position has been reached, the feeding of the remaining length of the strap is effected as it is necessary for a complete enclosure with strapping material of the respective package. This feeding movement is controlled by hand or likewise by means of heretofore known control means, such as limit switches.

A commercially available clamping and closing device is suspended on a tension spring system 30 which is displaceable on a profiled rail 29, this clamping and closing device being used for closing the strap.

The advantage of the present invention is seen in particular in the fast and trouble-free application of the strapping material and in the fact that an unnecessary pulling back of the strap is avoided.

It is, of course, to be understood that the present invention is, by no means, limited to the particular show ing in the drawing but also comprises any modifications ,within the scope of the appended claims.

What I claim is:

1. A method of strapping round packages of various diameters by means of a strap guided in strap guiding means, which includes in combination the step of: withdrawing a first strap section from a strap supply roll, advancing said strap section only into a portion of said strap guiding means, adapting the path for the strap in the strap guiding means to the circular contour of the package to be strapped, thereafter advancing the strap section withdrawn from the strap supply roll further through the adapted path of said strap guiding means so as to pass said strap completely around the package to be strapped, tightening the strap around the respective package, and locking said strap on the package to be strapped.

2. A method in combination according to claim 1, in which the first strap section pulled from a strap supply roll corresponds in length approximately to the circumference of the smallest diameter package to be strapped. 

1. A method of strapping round packages of various diameters by means of a strap guided in strap guiding means, which includes in combination the step of: withdrawing a first strap section from a strap supply roll, advancing said strap section only into a portion of said strap guiding means, adapting the path for the strap in the strap guiding means to the circular contour of the package to be strapped, thereafter advancing the strap section withdrawn from the strap supply roll further through the adapted path of said strap guiding means so as to pass said strap completely around the package to be strapped, tightening the strap around the respective package, and locking said strap on the package to be strapped.
 2. A method in combination according to claim 1, in which the first strap section pulled from a strap supply roll corresponds in length approximately to the circumference of the smallest diameter package to be strapped. 